With the current prevalence of computers, people frequently connect various types of accessory devices to their computers so as to realize additional or desired functions. The most common of these accessory devices include external hard drives, portable disks, video and audio players, external power supplies, mice and keyboards. However, when multi-media computers initially came to rise, the manufacturers of these computers did not reach a consensus on the specifications for the transmission interfaces of these accessory devices. For example, many printers can only be connected to an LPT port; many MODEMs can only be connected to RS232 ports, several types of mice and keyboards can only connect to a PS/2 ports, and so on. Further, these different interface specifications often require the installation of corresponding drivers and then rebooting of the computing device prior to use. This can be a source of significant inconvenience to consumers in terms of use, and also increases difficulties for computer manufacturers and accessory manufacturers in terms of coordination.
With this background in mind, the Universal Serial Bus (USB) interface supports both hot swapping and plug-and-play features. Hot swapping means the USB accessory device can be directly plugged/unplugged when the computer is running with the appropriate software, and this hot-swapping will not damage the host or USB accessory devices. Plug-and-play means the computer can detect and use the newly plugged-in accessory device in real time without the need of rebooting. Moreover, USB speeds are typically much higher than that of traditional standard interfaces, such as parallel ports (e.g. EPP, LPT) and serial ports (e.g. RS-232). With the above advantages and market demands, USB has now become a popularly accepted specification.
To date, the development of USB technology has gone through three major phases, from version 1.0 to version 3.0. Since the original USB plug only fits one specific way in the USB socket, the USB socket can be damaged if the user inserts the USB plug in the wrong direction. Further, it is somewhat troublesome to change and maintain the USB socket built into a host computer. Therefore, a fool-proof structure has been provided to protect against such reverse plugging. However, this structure is still a source of inconvenience for the user despite the fact that reverse plugging is avoided. Therefore, the newest USB 3.0 plug is designed to be able to be engaged in both orientations (i.e., up and down). Inserted in either way, it can electrically connect to the socket, which improves the previous structural design which only fits one way.
Due to the inconvenience related to maintenance or repairs of a USB socket, users and manufacturers actively seek to protect the USB socket to eliminate such maintenance-related troubles. However, in addition to the above orientation problems, there are also some other factors that may damage USB sockets, such as the resilient contact terminals inside the socket. After coupling the USB plug, the resilient contact terminals in the USB socket are pressed back by the engaging terminals of the USB plug, and resist the insertion pressure to elastically abut against the engaging terminals without any gaps, thus maintaining the electrical connection between the USB socket and the USB plug stable.
However, USB 3.0 is more compact than the previous USB 1.0 or 2.0 versions, and as a result the structure of the resilient contact terminals is more delicate and fine due to the greater numbers. If the resilient contact terminals are pressed improperly or used for a long time, the structure may be deformed, which can cause elastic fatigue or displacement. This can lead to gaps, interruption in the electrical connections between the engaging terminals and the resilient contact terminals, and reduction in the effectiveness of the USB accessory device. Additionally, many situations require using multiple USB accessory devices collaboratively. For example, clearing and sorting redundant or disordered data in a computer using an external hard drive requires three objects: the mouse, keyboard and external hard drive. In case of malfunction on any USB socket, the user must give up one of these three devices. Consequently, the user cannot finish the desired goal using an external hard drive. Some accessory devices also have large power requirements, and so they can occupy two neighboring USB sockets. If one of these sockets is broken, it can be a source of great inconvenience to the computer operator.
To continue to back up and clear the data in the computer, most users are forced to consider replacing the damaged USB socket. However, it is quite difficult for the users to change a USB socket because it requires disassembling the computer and checking the motherboard. Moreover, this kind of repair may take several days. Nowadays, people rely on computers to such a degree that they may feel it is not worth it to spend so much time on a small component, which would delay their work or entertainment.